Additive manufacturing of Zr-based metallic glass structures on 304 stainless steel substrates via V/Ti/Zr intermediate layers

Welding of dissimilar metals is challenging, particularly between crystalline metals and metallic glasses (MGs). In this study, Zr_65.7Cu_15.6Ni_11.7Al_3.7Ti_3.3 (wt%) MG structures were built on 304 stainless steel (SS) substrates by laser-foil-printing (LFP) additive manufacturing technology in which MG foils were laser welded layer-by-layer onto the SS substrate with a transition route, i.e., SS → V → Ti → Zr → MG. The direct welding of MG on SS would lead to the formation of various brittle intermetallics and the consequent peeling off of the welded MG foils from the SS substrate, which could be resolved via the use of V/Ti/Zr intermediate layers. The chemical composition, formed phases, and micro-hardness were characterized in the dissimilar joints by energy dispersive spectroscopy, X-ray diffraction, and micro-indentation. Since the intermediate materials were highly compatible with the base metals or the adjacent intermediate metals, undesirable intermetallics were not detected in the dissimilar joint. The bonding tensile strength between the SS substrate and the MG part with intermediate layers was measured about 477 MPa.